Flue Wellman-Lord process

SOXAL A flue-gas desulfurization process, basically similar to the Wellman-Lord process but regenerating the bisulfite solution in a membrane electrochemical cell. Developed by Allied Signal Group and piloted at the Florida Power Light Company, Miami, FL, in 1991. A larger demonstration plant was planned for Dunkirk, New York. 

The Wellman-Lord process uses the effective sodium sulfite-sodium bisulfite equilibrium to capture sulfur dioxide from flue gases [40] (Eqs. 3.26 and 3.27). 

In the industrial practice of gas treating, removal of one or more components of a gas stream by means of a chemically rea tive liquid is almost always accompanied by a process which r generates the rich liquid solution by stripping out the absorbed gas. The only important exception is flue gas desulfurization, where, often the product of the reaction (usually calcium sulfite and sulfate) is simply disposed of as waste however, also for flue gas desulfurization processes where a regeneration step is inclu ed, such as the Wellman-Lord process, are in common industrial use. 

Although it is possible to convert the SO2 removed from the flue gas to ammonium sulfate, sodium sulfate, or gypsum, the market for such by-products is quite restricted. More recently, interest has centered on processes that recover the SO2 in concentrated form. One such system, the Wellman Lord Process (licensed by Davy-McKee/Davy Corp. Pic.) uses a solution of sodium or potassium sulfite to absorb SO2. The liquid effluent contains a mixture of sulfites and bisulfites from which the less soluble bisulfites are crystallized. The recovered solids are heated to decompose the bisulfites to sulfites with the release of SO2. These sulfites then are redissolved in the liquid recycled to the scrubber. Only a... 

Giovanetti, A. 1992A, Flue Gas Desulfurization with the Wellman-Lord Process, unpresented technical paper, John Brown E C, Houston, TX, April 21. 

Wellman-Lord process A process used for flue gas desulphurization. Sulphur dioxide in the flue gas is absorbed in sodium sulphite in a wet spray scrubber column forming sodium bisulphite ... 

Wellman-Lord The most widely used regenerable flue-gas desulfurization process. The sulfur dioxide is absorbed in sodium sulfite solution in a wet spray scrubber, forming sodium bisulfite ... 

The adaptability of this sulfur dioxide reduction technology to a feed gas containing 100% sulfur dioxide (dry basis) will be demonstrated at the D. H. Mitchell Station of the Northern Indiana Public Service Co. (NIPSCO) at Gary, Indiana (8). In this application the process will be combined with the Wellman-Lord sulfur dioxide recovery process to provide a complete flue gas desulfurization system for a 115-MW coal-fired boiler in a project jointly funded by NIPSCO and the Environmental Protection Agency. 

Bailey, E. E., 1974, Continuing Progress for the Wellman-Lord SO2 Process, Proceedings Symposium on Flue Gas Desulfurization, Atlanta, GA, Nov. 4-7, Vol. n, EPA 650/2-74-126b, December, pp. 745-760,... 

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